A patient often may be dependent upon the manual assistance of caregivers changing the patient's position in bed. Patients who are mobility impaired because of either disease or accident live in a variety of settings, including hospitals, nursing homes, rehabilitation centers, hospices and their own homes. The inability to move in bed causes patient discomfort and may lead to the development of decubitus ulcers (bed sores). Regular periodic movement of the mobility impaired patient is thus necessary, but is a laborious task for the caregivers. The manual assistance by a caregiver in moving the patient often results in back injury to the caregiver. Frequently two or more aides are required to manually lift and reposition the patient. Furthermore, in medical settings such as hospitals and nursing homes, the task of repositioning a patient is time consuming, thereby reducing the time available for other patient care needs.
It has generally been known to mechanically turn the bed sheets or pad on which the patient lies. In particular numerous mechanized devices are available which turn the patient utilizing movement of an underlying soft, flexible material. All are mechanized variants of the turning sheet and pad positioned underneath the patient that was commonly used at the beginning of the century. When it became necessary to turn the patient, the caregiver would pull at the edges of the turning sheet and a frictional engagement would cause the patient to be rolled on the pad, such as disclosed in U.S. Pat. No. 1,334,901 issued to Higdin.
Another variant of a manual apparatus for positioning patients is provided in U.S. Pat. No. 4,872,226, issued to Lonardo. This apparatus includes a rectangular bed pad which is located on the bed surface and extends at least from above the shoulders of the patient to a point at least below the hip areas. It is fitted with a pair of straps which is secured to the pad to extend transversely across the pad in substantial alignment with the shoulders and hip areas of the patient. Various straps are attached to the pad to effect movement of the patient into a preselected position by pulling up the straps. This device is not mechanized and relies upon the caregiver to pull on hand gripping loops which are positioned at various points in the straps. Thus, the patient is once again positioned by manual effort from caregivers, which is strenuous, time consuming and may lead to back injury and to insurance or worker's compensation claims. Consequently, it frequently occurs that the patients are not turned as often as they should be, which results in serious health problems, such as bed sores. More recent variants of this apparatus utilize essentially the same principle, but have substituted a mechanized force for that previously exerted by the caregiver.
An example of a mechanized apparatus for turning a person confined to a bed is disclosed in U.S. Pat. No. 4,502,169, issued to Person. This apparatus includes an adjustable frame which is applied to a bed. This frame supports selectively rotatable rolls positioned at the level of the bed mattress. The rolls are connected to an electric motor. A draw sheet extends between the rolls, across the upper side of the bed and is wound on both rolls. The patient lies on top of the draw sheet. When electric motor is turned on by a patient or caretaker, the draw sheet is pulled in a preselected direction and the patient is turned by friction produced between the patient's body and the sheet. The efficacy of the turning force produced is dependent upon several external factors, including the size of the patient and the texture of the fabrics comprising the draw sheet and patient apparel. A more predictable and controllable turning mechanism is, therefore, desirable.
An additional drawback to the Persson device is that it is bulky, which tends to obstruct the patient's care and also the ability of the patient to be transferred into and out of the bed. Further, special linens are required and they may need to be changed frequently, especially in cases of incontinence. Because of the roller mechanism, changing linens is a time consuming chore.
In other arrangements, the bed assembly itself may turn so as to deposit the immobilized patient onto a separate mattress. An example of a turn over bed assembly is disclosed in U.S. Pat. No. 3,827,089 issued to Grove. It includes a mattress which is movably supported on a rotationally movable carrier frame. A patient lying on the lower mattress and who wishes to change position from face down to face up, or vice versa, is strapped by a caregiver to the mattress upon which the patient presently lies. Then, upon engagement of the controls by the caregiver, the assembly is rotated one quarter revolution. The mattress upon which the patient had been lying is secured for movement towards the opposite mattress, and then a succeeding quarter turn positions the patient in the desired new position on the opposing mattress. The mattress upon which the patient had previously been lying has been retracted on its support rails. The dual mattress apparatus is very bulky and quite expensive. Also, it has limited utility since the patient is either deposited face up or face down. To shift a patient to one side or the other still requires manual intervention by the caregivers.
A vast improvement over the prior art has been realized by applicant's own earlier invention described in U.S. Pat. No. 5,168,587. It uses a corset for surrounding the patient's torso. A pair of straps attached to each side of the corset are routed over the side railings of the bed and joined to a power take-up device located underneath the patient's bed. Operation of the power take-up device applies tension to one strap to effect rotation of the patient. Because of the location of the device unit beneath the bed frame, it has been found that applicant's earlier invention is not universally applicable to all hospital beds. Also, the side railings of some hospital beds are not sturdy enough to accommodate the stresses developed on them by the engagement of the straps therewith. For example, beds with separate side rails at the head and front of the bed lack necessary rigidity. Thus, a need exists for a less bulky, nonobstructive device which is universally applicable to most hospital beds now commonly in use.